Property and Equipment (Tables)
 12 Months Ended
Aug. 31, 2012
Property Plant And Equipment [Abstract]  
Components of Property and Equipment

Components of property and equipment are as follows:

 

     August 31,  
     2012     2011  
     (Dollars in thousands)  

Land and land improvements

    $ 11,623      $ 10,552   

Plant and equipment

      346,087        330,273   

Construction in progress

      7,679        6,375   
  

 

 

    

 

 

  
     365,389        347,200   

Accumulated depreciation

      (252,198 )      (239,828 ) 
  

 

 

    

 

 

  

Net property and equipment

    $ 113,191      $ 107,372